Heterologous expression of the yeast Tpo1p or Pdr5p membrane transporters in Arabidopsis confers plant xenobiotic tolerance

This deposit is composed by the main article plus the supplementary materials of the publication.Soil contamination is a major hindrance for plant growth and development. The lack of effective strategies to remove chemicals released into the environment has raised the need to increase plant resilience to soil pollutants. Here, we investigated the ability of two Saccharomyces cerevisiae plasma-membrane transporters, the Major Facilitator Superfamily (MFS) member Tpo1p and the ATP-Binding Cassette (ABC) protein Pdr5p, to confer Multiple Drug Resistance (MDR) in Arabidopsis thaliana. Transgenic plants expressing either of the yeast transporters were undistinguishable from the wild type under control conditions, but displayed tolerance when challenged with the herbicides 2,4-D and barban. Plants expressing ScTPO1 were also more resistant to the herbicides alachlor and metolachlor as well as to the fungicide mancozeb and the Co(2+), Cu(2+), Ni(2+), Al(3+) and Cd(2+) cations, while ScPDR5-expressing plants exhibited tolerance to cycloheximide. Yeast mutants lacking Tpo1p or Pdr5p showed increased sensitivity to most of the agents tested in plants. Our results demonstrate that the S. cerevisiae Tpo1p and Pdr5p transporters are able to mediate resistance to a broad range of compounds of agricultural interest in yeast as well as in Arabidopsis, underscoring their potential in future biotechnological applications.Fundação para a Ciência e a Tecnologia grants: (EXPL/AGR-PRO/1013/2013, PTDC/BIA-PLA/1084/2014, SFRH/BPD/44640/2008, SFRH/BPD/81221/2011, PD/BD/105735/2014, PD/00133/2012, SFRH/BD/92552/2013, UID/BIO/04565/2013, UID/Multi/04551/2013). Programa Operacional Regional de Lisboa 2020 grant: (Project N. 007317).info:eu-repo/semantics/publishedVersio

Age protects from harmful effects produced by chronic intermittent hypoxia

Producción CientíficaObstructive sleep apnoea (OSA) affects an estimated 3–7% of the adult population, the frequency doubling at ages >60–65 years. As it evolves, OSA becomes frequently associated with cardiovascular, metabolic and neuropsychiatric pathologies defining OSA syndrome (OSAS). Exposing experimental animals to chronic intermittent hypoxia (CIH) can be used as a model of the recurrent hypoxic and O2 desaturation patterns observed in OSA patients. CIH is an important OSA event triggering associated pathologies; CIH induces carotid body (CB)-driven exaggerated sympathetic tone and overproduction of reactive oxygen species, related to the pathogenic mechanisms of associated pathologies observed in OSAS. Aiming to discover why OSAS is clinically less conspicuous in aged patients, the present study compares CIH effects in young (3–4 months) and aged (22–24 months) rats. To define potential distinctive patterns of these pathogenic mechanisms, mean arterial blood pressure as the final CIH outcome was measured. In young rats, CIH augmented CB sensory responses to hypoxia, decreased hypoxic ventilation and augmented sympathetic activity (plasma catecholamine levels and renal artery content and synthesis rate). An increased brainstem integration of CB sensory input as a trigger of sympathetic activity is suggested. CIH also caused an oxidative status decreasing aconitase/fumarase ratio and superoxide dismutase activity. In aged animals, CIH minimally affected CB responses, ventilation and sympathetic-related parameters leaving redox status unaltered. In young animals, CIH caused hypertension and in aged animals, whose baseline blood pressure was augmented, CIH did not augment it further. Plausible mechanisms of the differences and potential significance of these findings for the diagnosis and therapy of OSAS are discussed.Ministerio de Ciencia, Innovación y Universidades (grant BFU2012-37459)Instituto de Salud Carlos III (grant CIBER CB06/06/0050)Portuguese Foundation for Science and Technology (grant EXP/NEU-SCC/2813/2013

Chemical recycling of plastics assisted by microwave multi-frequency heating

Handling plastic waste through recycling allows extending the life of polymeric materials, avoiding recurrence to incineration or landfilling. In contrast with traditional mechanical recycling technologies, chemical recycling enables the obtention of the virgin monomers by means of depolymerisation to create new polymers with the same mechanical and thermal properties as the originals. Research presented in this paper is part of the polynSPIRE project (Horizon 2020 European funding programme) and develops and scales-up a heated reactor to carry out the depolymerisation of polyamide-6 (PA6), polyamide-6, 6 (PA66) and polyurethane (PU) using microwave (MW) technology as the heating source. The purpose is to design and optimize a MW reactor using up to eight ports emitting electromagnetic waves. Finite element method (FEM) simulation and optimisation are used to design the reactor, considering as parameters the data obtained from experimental dielectric testing and lab-scale characterisation of the processes and materials studied. Two different COMSOL Multiphysics modules are involved in this work: Radio Frequency (RF) and Chemical Reaction Engineering (RE), to simulate the reactor cavity using two frequency levels (915 MHz and 2.45 GHz) with a power level of 46 kW, and the chemical depolymerisation process, respectively. A sensitivity study has been performed on key parameters such as the frequency, the number of ports, and position inside the reactor to consolidate the final design. It is expected that these results assist in the design and scale-up of microwave technology for the chemical recycling of plastics, and for the large-scale deployment of this sustainable recovery alternative. © 2021 The Author

Evaluation of microflow configurations for scale inhibition and serial X-ray diffraction analysis of crystallization processes

The clean and reproducible conditions provided by microfluidic devices are ideal sample environments for in situ analyses of chemical and biochemical reactions and assembly processes. However, the small size of microchannels makes investigating the crystallization of poorly soluble materials on-chip challenging due to crystal nucleation and growth that result in channel fouling and blockage. Here, we demonstrate a reusable insert-based microfluidic platform for serial X-ray diffraction analysis and examine scale formation in response to continuous and segmented flow configurations across a range of temperatures. Under continuous flow, scale formation on the reactor walls begins almost immediately on mixing of the crystallizing species, which over time results in occlusion of the channel. Depletion of ions at the start of the channel results in reduced crystallization towards the end of the channel. Conversely, segmented flow can control crystallization, so it occurs entirely within the droplet. Consequently, the spatial location within the channel represents a temporal point in the crystallization process. Whilst each method can provide useful crystallographic information, time-resolved information is lost when reactor fouling occurs and changes the solution conditions with time. The flow within a single device can be manipulated to give a broad range of information addressing surface interaction or solution crystallization

Highly Productive Continuous Flow Synthesis of Di- and Tripeptides in Water

The reaction of amino acid derived N-carboxyanhydrides (NCAs) with unprotected amino acids under carefully controlled aqueous continuous flow conditions realized the formation of range of di- and tripeptide products in 60-85% conversion at productivities of up to 535 g.L-1h-1. This required a fundamental understanding of the physicochemical aspects of the reaction resulting in the design of a bespoke continuous stirred tank reactor (CSTR) with continuous solids addition, high shear mixing, automated pH control to avoid the use of buffer, and efficient heat removal to control the reaction at 1±1 °C

Epidemiological Algorithm and Early Molecular Testing to Prevent COVID-19 Outbreaks in a Mexican Oncologic Center

Introduction: Prevention strategies and detection of latent COVID-19 infections in oncology staff and oncologic patients are essential to prevent outbreaks in a cancer center. In this study, we used two statistical predictive models in oncology staff and patients from the radiotherapy area to prevent outbreaks and detect COVID-19 cases. Methods: Staff and patients answered a questionnaire (electronic and paper surveys, respectively) with clinical and epidemiological information. The data was collected through two online survey tools: Real-Time Tracking (R-Track) and Summary of Factors (S-Facts). According to the algorithm\u27s models, cut-off values were established. SARS-CoV-2 qRT-PCR tests confirmed the algorithm\u27s positive individuals. Results: Oncology staff members (n=142) were tested, and 14% (n=20) were positives for the R-Track algorithm; 75% (n=15) were qRT-PCR positive. The S-Facts algorithm identified 7.75% (n=11) positive oncology staff members, and 81.82% (n=9) were qRT-PCR positive. Oncology patients (n=369) were evaluated, and 1.36% (n=5) were positive for the algorithms. The 5 patients (100%) were confirmed by qRT-PCR at a very early stage. Conclusions: The proposed algorithms could prove to become an essential prevention tool in countries where qRT-PCR tests and vaccines are insufficient for the population

Análisis de la composición química de los cementos tipo MTA y PORTLAND tipo I

El propósito de este estudio es evaluar la composición química de tres cementos: Portland tipo I (CEMEX-Samper®, Cundinamarca, Colombia), Portland tipo I (CEMEX-Diamante®, Ibagué, Colombia) y ProRoot MTA® (Dentsply-Maillefer, Ballaigues, Suiza). Se utilizó una muestra probabilística de 17 pastillas para cada tipo de cemento. El análisis se llevó a cabo con la microsonda EDAX (Mahwah, NJ, USA) del microscopio de barrido electrónico SEM FEI (Quanta 200, Hillsboro, Oregon USA), bajo condiciones estandarizadas de lectura de las muestras Se hicieron cuatro lecturas por muestra, para un subtotal de 68 lecturas por cada tipo de cemento y un total de 208 lecturas. Los resultados se obtuvieron en porcentaje de peso sólido por elemento. Los datos generales fueron analizados por las pruebas ANOVA, comparaciones múltiples de Tukey y t de Student. Se observaron tres elementos comunes entre los tres cementos: Ca, Si y Al, pero se encontraron diferencias estadísticamente significativas de los elementos comunes entre el cemento ProRoot MTA® y los cementos Portland I. El Bi solo se encontró en el ProRoot MTA y el S solo se encontró en los cementos Portland tipo I. Se concluye que la composición de los tres cementos es similar. Sin embargo, es necesario evaluar el impacto que puede tener, tanto la presencia de S en los cementos Portland I, como la diferencia de concentraciones de los elementos que fueron comunes en los tres cementos en cuanto a biocompatibilidad y efectividad clínic